2004.08.20 08:25 "[Tiff] Tiff conversion using libtiff", by Ross A. Finlayson

2004.08.20 08:56 "Re: [Tiff] Tiff conversion using libtiff", by Joris Van Damme

Ross,

Here is a section of the code in the tiff2pdf.c file that checks when the PhotometricIntepretation field is RGB that the number of samples is 3, for Red, Green, and Blue:

Presumably, PhotometricInterpretation = RGB and SamplesPerPixel = 1 could even be a valid combination, if and only if the Indexed tag is also present. See

http://partners.adobe.com/asn/developer/pdfs/tn/TIFFPM6.pdf#page=11

or

http://www.awaresystems.be/imaging/tiff/tifftags/indexed.html

I must admit I have never seen such 'Indexed' image in the wild, so I'm looking forward to a tiffinfo or whatever tag dump. Note that it might not be a good idea to fool LibTiff into thinking PhotometricInterpretation = Palette without checking for presence of Indexed first.

Hey I've been developing Yet Another TIFF Tag Viewer

Cheers!

I've noticed that on Joris' web page there are still yet a few private tags that I did not know of, see http://www.awaresystems.be/imaging/tiff/tifftags.html.

Likewise, your list contains a lot that I didn't yet have any data on.

And thanks for the pointer. Indeed, since yesterday, a 'TIFF Tag Reference' is on-line. Anyone with remarks, thoughts, wishes, or willing to submit specifications on private tags, should contact me at joris.at.lebbeke@skynet.be.

Have a nice day,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html